Timing and Composition of Last Meal before Bedtime Affect Sleep Parameters of Night Workers

Round 1

Reviewer 1 Report

The authors considerably improved this manuscript following main concerns from the reviewers, the manuscript is recommended for publication.

Author Response

We appreciate the opportunity to once again improve the quality of the manuscript based on the suggestions presented by the reviewers. Thank you so much.

Reviewer 2 Report

This study explores the relationships of timing and content of last meal before bedtime and actigraphic characteristics of daytime and nighttime sleep in shift workers. They found significant associations of the interval between the last meal and sleep onset and diurnal sleep duration, and between intake of fat and carbohydrate with latency to onset of diurnal sleep.

“These findings suggest that both timing and composition of the last meal before bedtime are key factors for good diurnal and nocturnal sleep among night-shift workers.” Too strong claim.

I think the authors adequately responded to the comments of other reviewers to their initial version of this manuscript, and now the manuscript can be published in the journal in its present (revised) form.

Author Response

We appreciate the opportunity to once again improve the quality of the manuscript based on the suggestions presented by the reviewers. Thank you so much.

Reviewer 3 Report

Comments to Author:
Nogueira et. al., present the timing and composition of last meal before bedtime affect sleep parameters of night workers. Since this study was highly inclusive in selecting their subjects; the authors provide strong evidence that composition of last meal affects sleep parameters of night workers. The paper presents high quality data. Such work is much needed and valued in the field. Seems highly appropriate for clocks and sleep. Overall, the paper is well written; however, there are few minor points to address prior to publication as summarized below.

Some minor suggestions/comments:

• Figure1(a, b & C) provide title of Y-axis with unit (e.g., hr/min/days)
• Although in the discussion section author has mentioned that “results cannot be generalized to other types of shift workers”. It’s because this study was inclusive in nature, therefore author must provide other evidence and references in their discussion which strengthen this argument.
• 7/41 references are from author’s: a total of 17% of self-citation. This can be reduced to <5%

Author Response

We appreciate the opportunity to once again improve the quality of the manuscript “Timing and composition of the last meal before bedtime affects sleep parameters of night workers” based on the suggestions presented by the reviewers. We have addressed all the comments and we believe the text has become clearer and more complete.

            All changes made are highlighted in red in the manuscript, and responses to comments are as follows:

1) “These findings suggest that both timing and composition of the last meal before bedtime are key factors for good diurnal and nocturnal sleep among night-shift workers.” Too strong claim.

• Thank you for the observation. The sentence was modified both in the abstract and the main text as follows: “These findings suggest that both timing and composition of the last meal before bedtime may be potential key factors for good diurnal and nocturnal sleep among night-shift workers.”

2) Figure 1 (a, b & C) provide title of Y-axis with unit (e.g., hr/min/days).

• Thank you for the observation. Axis’ titles were added as requested.

3) Although in the discussion section author has mentioned that “results cannot be generalized to other types of shift workers”. It’s because this study was inclusive in nature, therefore author must provide other evidence and references in their discussion which strengthen this argument.

• Thank you for the observation. The following studies, which reinforce the affirmation highlighted by the reviewer, were added as references:

11. Della Torre, S.B.; Wild, P.; Dorribo, V.; Danuser, B.; Amati, F. Energy, nutrient and food intakes of male shift workers vary according to the schedule type but not the number of nights worked. Nutrients 2020, 12, 919, doi:10.3390/nu12040919
12. Heath, G.; Dorrian, J.; Coates, A. Associations between shift type, sleep, mood, and diet in a group of shift working nurses. Scand J Work Environ Health 2019, 45, 4, 402-412. doi:10.5271/sjweh.3803
13. Lopez-Minguez, J.; Gómez-Abellán, P.; Garaulet, M. Timing of breakfast, lunch, and dinner. Effects on obesity and metabolic risk. Nutrients 2019, 11, 2624. doi:10.3390/nu11112624

4) 7/41 references are from author’s: a total of 17% of self-citation. This can be reduced to <5%.

• Self-citation was reduced to 9% (4/42). It was not possible to reduce it to <5% as suggested by the reviewer in order not to impair the quality and consistency of the manuscript.

Once again, we thank you for your valuable contributions and are available for any necessary clarifications.

Round 2

Reviewer 3 Report

Minor comment.

1. I still don't see y-axis title on Figure 1a,b and in c. Author must put title on y-axis.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

The authors studied meal and sleep timing in 38 female nurses to evaluate the interval between the last meal and bedtime on workdays and days-off and relationship of diurnal and nocturnal sleep parameters with the characteristics of this meal. They found similar phase angle between the time for last meal and bedtime on workdays and days-off, and a negative influence of inadequate intake of protein close to the diurnal sleep episode on quality of sleep during this episode (e.g., a longer sleep onset latency).  They concluded that both timing and the composition of the last meal before bedtime are key factors for good quality sleep in night workers, especially on the day after a night shift. I think the manuscript desires publication in its present form.

 

I think the authors addressed the majority of reviewers' concerns

Author Response

We appreciate the opportunity to improve the quality of the manuscript and thank the reviewer for the comments.

Reviewer 2 Report

The authors considerably improved this manuscript following main concerns from the reviewers, I think the paper can be accepted as it is.

Author Response

We appreciate the opportunity to improve the quality of the manuscript and thank the reviewer for the comments.